Near and Far Interaction for Augmented Reality Tree Visualization Outdoors

The implementation of augmented reality in nature and in an environmental education context, is not a common case. Furthermore, augmented reality is often used basically for visualization, which puts users in a rather passive state. In this paper we investigate how near and far interaction using a head-mounted-display can be combined with visualization on a tree outdoors and which of the interaction techniques are suitable for a future use in an environmental education application. We examine the interaction with virtual leaves on the floor combined with a virtual-real interaction with a real tree. Parameters like type of interaction, different real surroundings and time task performance, as well the interplay and connection between them are discussed and investigated. Additionally, process visualization in a nature setting like clouds and rain, and growing of tree roots are included in the augmented reality modules and evaluated in user tests followed by a questionnaire. The results indicate, that for a future educational application both, near and far interaction, can be beneficial.